Salmonellosis. Diagnosis of major poultry diseases

Authors: Gast, Richard; WALTMAN, DOUGLAS - Georgia Poultry Laboratory Network

Submitted to: Book Chapter
Publication Type: Book / Chapter
Publication Acceptance Date: 12/1/2017
Publication Date: 2/1/2018
Citation: Gast, R.K., Waltman, D.W. 2018. Salmonellosis. Diagnosis of major poultry diseases. Y.J. Saif and H. Toro, eds.pp. 55-59. Servet Publishing, Zaragoza, Spain.

Interpretive Summary:

Technical Abstract: The bacterial genus Salmonella is responsible for economically significant acute and chronic poultry diseases and is a leading public health threat via the contamination of poultry meat and eggs. Significant government and industry resources are invested in testing and control efforts to control Salmonella infections in poultry flocks. Two nonmotile Salmonella serovars are host-specific for avian species and cause systemic disease in immature (Pullorum disease, caused by S. Pullorum) or adult (Fowl typhoid, caused by S. Gallinarum) poultry. The numerous motile and non-host-adapted serovars are widely distributed in wild and domestic animal populations and are important agents of food-borne transmission of illness to humans. These “paratyphoid” salmonellae infrequently cause acute systemic disease except when highly susceptible chicks or poults are subjected to stressful conditions (crowding, poor environmental sanitation, feed or water deprivation, or extreme temperatures). However, they are highly prevalent in commercial poultry and colonization of the intestinal tract or internal organs can result in contamination of finished carcasses or eggs. Salmonellae can be introduced into poultry flocks by vertical transmission through contaminated eggs laid by infected hens or as a result of persistent environmental contamination in poultry housing facilities. Infection can spread by direct bird-to-bird contact, ingestion of contaminated feed, feces, or litter, airborne circulation of contaminated dust or aerosols, movement of contaminated equipment or personnel, and biological vectors (insects and rodents). Coordinated and sustained application of comprehensive risk reduction programs, incorporating multiple interventions along the production continuum, has made progress against Salmonella in poultry. Targeted testing to detect epidemiologically important serovars and vaccination to reduce the susceptibility of flocks to infection are used to augment good sanitation and biosecurity practices.